1H NMR technique, optical spectrophotometry and molecular dynamics simulations have been applied to study the effect of the lipid composition on emodin interaction with the lipid bilayer. The special attention was paid on the presence of the unsaturated fatty acid linoleic acid in the lipid bilayer. Emodin (1,3,8‐trihydroxy‐6‐methylanthraquinone) is a natural anthraquinone which shows a wide spectrum of biological activity including anticancer, anti-inflammatory, antiviral, antibacterial, neuroprotective and others. It is assumed that the location of emodin in the lipid membrane is important for its biological activity. It was demonstrated that in the presence of linoleic acid, the pKa value of the emodin significantly increases. Molecular dynamics simulations show that these changes can be associated with the interaction of emodin and linoleic acid inside the bilayer. Also, it was shown that the order of deprotonation positions in the POPC bilayer differs from the deprotonation order in aqueous solution.

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大黄素与磷脂双分子层和亚油酸相互作用的实验和理论研究

1H NMR 技术、光学分光光度法和分子动力学模拟已被应用于研究脂质成分对大黄素与脂质双层相互作用的影响。特别关注脂质双层中不饱和脂肪酸亚油酸的存在。Emodin (1,3,8-trihydroxy-6-methylanthraquinone) 是一种天然蒽醌，具有广泛的生物活性，包括抗癌、抗炎、抗病毒、抗菌、神经保护等。据推测，大黄素在脂质膜中的位置对其生物活性很重要。结果表明，在亚油酸的存在下，大黄素的 pKa 值显着增加。分子动力学模拟表明，这些变化可能与双层内大黄素和亚油酸的相互作用有关。此外，研究表明，POPC 双层中去质子化位置的顺序与水溶液中的去质子化顺序不同。